1. Field of the Invention
The present invention relates to electric outlets and, more specifically, to a shielding cap mounting arrangement for electric outlet, which enables the shielding cap to be moved horizontally to close/open the plugholes.
2. Description of the Related Art
FIG. 1 illustrates a conventional electric extension cable in which a shielding cap 12 is used and fastened to the vacant socket 1 to keep the respective plugholes 11 from sight, preventing insertion of external objects into the plugholes 11 by a child. The shielding cap 12 has bottom rods corresponding to the plugholes 11 for installation. When in use, the user must remove the corresponding shielding cap 12 from the socket 1 so that the electric plug can be inserted into the socket 1. After removable of the shielding cap 12 from one socket 1 of electric outlet, the shielding cap 12 must be properly received. Because the shielding cap 12 is a small item, it tends to be lost somewhere after removal from the corresponding socket 1 of the electric outlet. Further, it is inconvenient to mount and dismount the shielding cap 12 frequently.
In order to eliminate the aforesaid drawbacks, various safety electric outlets have been disclosed. These safety electric outlets have a safety structure on the inside, which prevents direct contact of inserted external object(s) with the internal electric contacts. When using these electric outlets, a supplementary device, for example, a push rod, plug pin, spring, etc., is used with the inserted electric plug to open the passage between the plugholes and the corresponding electric contacts in the electric socket, enabling the metal blades of the electric plug to be set into contact with the respective electric contacts in the socket to close the circuit. However, providing a safety structure in an electric socket must change the positioning or structure of the original electric contacts in the electric socket. Further, the installation of the safety structure complicates the fabrication of the electric socket and, may increase the dimensions of the electric socket.
FIGS. 2Axcx9c2C illustrates the use of a shielding cap 23 in an electric outlet 2 to close/open the plugholes of an electric socket 21. As illustrated, each electric socket 21 of the electric outlet 2 has a top recess 22 and two sliding grooves 221 horizontally disposed in the top recess 22 at two sides. The shielding cap 23 is inserted into the top recess 22, having two protruded coupling portions 231 respectively coupled to the sliding grooves 221. After installation in the top recess 22 of the electric socket 21, the shielding cap 23 can be moved horizontally along the sliding grooves 221 back and forth to close/open the plugholes in the top recess 22. This design still has drawbacks. In order to let the shielding cap 23 be easily coupled to the top recess 22, the length of the protruded coupling portions 231 is limited. However, the protruded coupling portions 231 tend to be forced out of the sliding grooves 221 when operating the shielding cap 23.
FIGS. 3Axcx9c3C show still another design of electric outlet and shielding cap arrangement according to the prior art. According to this design, each electric socket 31 of the electric outlet 2 has a top recess 32 and two sliding grooves 321 in the top recess 32; the shielding cap 33 has two bottom hooks 331 respectively hooked in the sliding grooves 321. After installation, the shielding cap 33 can be moved horizontally in the top recess 32 between two positions to close/open the plugholes in the top recess 32. This design is still not satisfactory in function. When moving the shielding cap 33, the bottom hooks 331 tend to be deformed or damaged, thereby causing the shielding cap 33 to be forced out of the top recess 32.
The present invention has been accomplished to provide a shielding cap mounting arrangement for electric outlet, which eliminates the aforesaid problems. It is one object of the present invention to provide a shielding cap mounting arrangement for electric outlet, which enables the shielding cap to be easily horizontally loaded in the electric outlet and moved horizontally between two positions to close/open the plugholes. It is another object of the present invention to provide a shielding cap mounting arrangement for electric outlet, which has means to indicate the positioning of the shielding cap. According to one aspect of the present invention, the electric outlet has a shell, a top recess in the shell, a set of plugholes in the top recess for receiving an electric plug, two rails at two sides of the top recess, two parallel sliding grooves respectively defined in the rails at two sides of the top recess, and two downward protruding portions downwardly protruded from the rails on the middle at an outer side; the shielding cap is mounted in the top recess between the downward protruding portions and moved along the sliding grooves to close/open the plugholes, having two side wings respectively horizontally inserted into the sliding grooves and suspended below the downward protruding portions to guide movement of the shielding cap in the top recess and to prohibit the shielding cap from escaping out of the top recess. According to another aspect of the present invention, the side wings of the shielding cap have respective front and rear sides disposed in flush with the distal ends of the side rails when the shielding cap moved to the open position to open the plugholes.